The goal of this Research Career Development Award (K01) is to provide the PI with a 5-year period of coursework and mentored research in the areas of sophisticated longitudinal data analytic techniques and data collection so that she develops the expertise necessary to pursue an independent research career examining associations between internalizing disorders and substance use and disorders. The first training goal focuses on gaining expertise in a number of longitudinal statistical analysis techniques (e.g., growth curve modeling, latent transition analysis) and will be achieved through a combination of coursework and mentored research. These techniques will initially be applied to two longitudinal archival data sets, the Minnesota Twin Family Study and the Pittsburgh Youth Study (Years 1-4). The second training goal involves mentored data collection;frequent assessments of a sample of disadvantaged youth in Camden, New Jersey will be conducted (Years 4-5). In Year 5 of this career development award, the PI will apply her statistical expertise to her own longitudinal data from the Camden study and apply for an R01 grant to expand her Camden Longitudinal Study and examine emerging questions relating to psychopathology and substance use problems. The proposed research examines longitudinal associations between internalizing disorders (depression, generalized anxiety, and social anxiety) and substance use and disorders (abuse and dependence). Direct examinations of two important potential moderators of these associations-gender and antisocial behavior- will be included and are viewed as crucial to developing an accurate understanding of longitudinal pathways between and among these problems. By using sophisticated longitudinal statistical techniques that are both variable-centered and person-centered and by using three complementary data sets, the research conducted during the 5-year period of this career development award will result in a comprehensive model of the longitudinal associations between internalizing disorders and substance use and disorders and will enable the PI to proceed onto an independent, highly productive program of research that propels the field to a deeper and more thorough understanding of the associations between psychopathology and substance use problems over time. This research is important to public health because a clear understanding of the associations between mental health and substance use problems will lead to more effective and targeted prevention and intervention efforts, thereby reducing the burden of mental illness and substance use problems on society.